code: def _getGradientOrNone(op_proto):
      try:
          grad_ops, _ = gradient_checker.getGradientForOp(op_proto)
          return grad_ops
      except Exception:
          return []
  
imports: import inspect
  import os
  import shutil
  import sys
  import tempfile
  import threading
  from contextlib import contextmanager
  from zipfile import ZipFile
  import argparse
  import hypothesis
  import numpy
  import caffe2.python.hypothesis_test_util
  from caffe2.proto import caffe2_pb2
  from caffe2.python import gradient_checker
  from caffe2.python.serialized_test import coverage
label_desc: Use image node_id 2 for calling a global function with example usage: _getGradientOrNone(op_proto) and returns: grad_ops, list